[理工] [工數]-變係數ode
作者: winer8 (快來明星3 缺1 ) 看板: Grad-ProbAsk
標題: [理工] [工數]-變係數ode
時間: Fri Aug 21 23:45:05 2009
xy"+2y'-xy=2e^x
答案是C1(1/x)e^x+C2(1/x)e^(-x)+e^x
我是用Q-1/4P^2-1/2P'算 到最後出現
1/(D^2-1) *2 e^x/(xlnx^-1) 就不會積了
另一題是(1-x^2)y"-2y'+2y=0 我怎麼算都不對
已知y=x為一解
答案是=k1[2+xln[(x-1)/(x+1)]]+k2x
真的感謝各位了
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